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关键词： monocot chimeric jacalin   lectin   OsJAC1   dirigent domain   melting point   carbohydrate-binding  

摘要： The monocot chimeric jacalin OsJAC1 from Oryza sativa consists of a dirigent and a jacalin-related lectin domain. The corresponding gene is expressed in response to different abiotic and biotic stimuli. However, there is a lack of knowledge about the basic function of the individual domains and their contribution to the physiological role of the entire protein. In this study, we have established a heterologous expression in Escherichia coli with high yields for the full-length protein OsJAC1 as well as its individual domains. Our findings showed that the secondary structure of both domains is dominated by beta-strand elements. Under reducing conditions, the native protein displayed clearly visible transition points of thermal unfolding at 59 and 85 degrees C, which could be attributed to the lectin and the dirigent domain, respectively. Our study identified a single carbohydrate-binding site for each domain with different specificities towards mannose and glucose (jacalin domain), and galactose moieties (dirigent domain), respectively. The recognition of different carbohydrates might explain the ability of OsJAC1 to respond to different abiotic and biotic factors. This is the first report of specific carbohydrate-binding activity of a DIR domain, shedding new light on its function in the context of this monocot chimeric jacalin.

关键词： Almond   In vitro   Micrografting   Micropropagation   Rootstock  

摘要： Grafted fruit trees are made up of two parts, the scion and the rootstock. The rootstocks affect the growth and physiological and biochemical treats of scion. The use of grafting technique in vitro produces healthy plants and allows careful study of rootstock and scion interactions. The objective of this research was to achieve a successful protocol for micrografting of the late-flowering Sahand cultivar on two wild almond rootstocks (Badam Kohi and Arjan) and also to determine the best rootstock for mentioned cultivar. In this regard, a factorial experiment was conducted to investigate the effect of rootstock type, culture medium (MD1 = MS, MD2 = MS +0.49 mu M IBA + 2.2 mu M BA, MD3 = MS + 2.46 mu M IBA + 0.44 mu M BA) and supporting system (paper bridge and perlite) on micrografting success of 'Sahand' scion. The results showed that in micrograft combination of 'Sahand'/Badam kohi, the highest grafting success (100%) and scion length (27.8 mm) were achieved on the MD2 medium with perlite. The Arjan rootstock increased electrolyte leakage and decreased total chlorophyll of the scion in compare to Badam Kohi rootstock. In the grafted combinations, the highest amount of superoxide dismutase, peroxidase and catalase activities were recorded in 'Sahand' on the Badam Kohi rootstock which were significantly higher than in the same scion on Arjan rootstock. It can be concluded that Badam Kohi is more suitable than Arjan as a rootstock for Sahand cultivar. Key message In vitro wedge micrografting was successfully established for Sahand cultivar on wild almond rootstocks using IBA and BA combinations in culture media. Badam Kohi rootstock supported 'Sahand' scion by induced more antioxidant enzymes than Arjan rootstock.

关键词： Coastal waters   Environmental toxicology   Risk assessment   Warfarin   Dexamethasone   Imidazole   Invertebrates   Gene expression   Antioxidant enzymes  

摘要： Pharmaceuticals represent a group of emerging contaminants. The short-term effect (3 and 7 days) of warfarin (1 and 10 mg L-1), dexamethasone (0.392 and 3.92 mg L-1) and imidazole (0.013 and 0.13 mg L-1) exposure was evaluated on mussels (Mytilus galloprovincialis). Total antioxidant status, glutathione reductase, glutathione peroxidase (GPx) and superoxide dismutase enzyme activities, and the expression of genes involved in the xenobiotic response (ATP binding cassette subfamily B member 1 (abcb1) and several nuclear receptor family J (nr1j) isoforms), were evaluated. All nr1j isoforms are suggested to be the xenobiotic receptor orthologs of the NR1I family. All drugs increased GPx activity and altered the expression of particular nr1j isoforms. Dexamethasone exposure also decreased abcb1 expression. These findings raised some concerns regarding the release of these pharmaceuticals into the aquatic environment. Thus, further studies might be needed to perform an accurate environmental risk assessment of these 3 poorly studied drugs.

关键词： Klenow fragment   DNA exonuclease   DNA endonuclease   Manganese   Pre-steady-state kinetics   Deinococcus radiodurans  

摘要： Deinococcus radiodurans survives extraordinary doses of ionizing radiation and desiccation that cause numerous DNA strand breaks. D. radiodurans DNA polymerase A (DrPolA) is essential for reassembling the shattered genome, while its biochemical property has not been fully demonstrated. In this study, we systematically examined the enzymatic activities of DrPolA and characterized its unique features. DrPolA contains an N-terminal nuclease domain (DrPolA-NTD) and a C-terminal Klenow fragment (KlenDr). Compared with the Klenow fragment of E. coli Pol I, KlenDr shows higher fidelity despite the lacking of 5 '-3 ' exonuclease proofreading activity and prefers double-strand DNA rather than Primer-Template substrates. Apart from the well-annotated 5 '-3 ' exonuclease and flap endonuclease activities, DrPolA-NTD displays approximately 140-fold higher gap endonuclease activity than its homolog in E. coli and Human FEN1. Its 5 '-3 ' exonuclease activity on ssDNA, gap endonuclease, and Holliday junction cleavage activities are greatly enhanced by Mn2+. The DrPolA-NTD deficient strain shows increased sensitivity to UV and gamma-ray radiation. Collectively, our results reveal distinct biochemical characteristics of DrPolA during DNA degradation and re-synthesis, which provide new insight into the outstanding DNA repair capacity of D. radiodurans. (C) 2021 Elsevier B.V. and Societe Francaise de Biochimie et Biologie Moleculaire (SFBBM). All rights reserved.

关键词： Mimosine   β   –   PA   Willardiine   Isowillardiine   Lathyrine   Serine   OAS   Cysteine synthase  

摘要： Plants catalyze the biosynthesis of a large number of non-protein amino acids, which are usually toxic for other organisms. In this review, the chemistry and metabolism of N-heterocyclic non-protein amino acids from plants are described. These N-heterocyclic non-protein amino acids are composed of beta-substituted alanines and include mimosine, beta-pyrazol-1-yl-l-alanine, willardiine, isowillardiine, and lathyrine. These beta-substituted alanines consisted of an N-heterocyclic moiety and an alanyl side chain. This review explains how these individual moieties are derived from their precursors and how they are used as the substrate for biosynthesizing the respective N-heterocyclic non-protein amino acids. In addition, known catabolism and possible role of these non-protein amino acids in the actual host is explained.

关键词： Sanfilippo syndrome type B   Mucopolysaccharidosis IIIB   Intracerebroventricular enzyme replacement therapy (ICV-ERT)   Heparan sulfate   Neonatal mice  

摘要： Mucopolysaccharidosis IIIB (MPS IIIB, Sanfilippo syndrome type B) is caused by a deficiency in alpha-N-acetylglucosaminidase (NAGLU) activity, which leads to the accumulation of heparan sulfate (HS). MPS IIIB causes progressive neurological decline, with affected patients having an expected lifespan of approximately 20 years. No effective treatment is available. Recent pre-clinical studies have shown that intracerebroventricular (ICV) ERT with a fusion protein of rhNAGLU-IGF2 is a feasible treatment for MPS IIIB in both canine and mouse models. In this study, we evaluated the biochemical efficacy of a single dose of rhNAGLU-IGF2 via ICV-ERT in brain and liver tissue from Naglu(-/-) neonatal mice. Twelve weeks after treatment, NAGLU activity levels in brain were 0.75-fold those of controls. HS and beta-hexosaminidase activity, which are elevated in MPS IIIB, decreased to normal levels. This effect persisted for at least 4 weeks after treatment. Elevated NAGLU and reduced beta-hexosaminidase activity levels were detected in liver;these effects persisted for up to 4 weeks after treatment. The overall therapeutic effects of single dose ICV-ERT with rhNAGLU-IGF2 in Naglu(-/-) neonatal mice were long-lasting. These results suggest a potential benefit of early treatment, followed by less-frequent ICV-ERT dosing, in patients diagnosed with MPS IIIB. (C) 2021 Elsevier Inc. All rights reserved.

关键词： Prostate cancer   Robotic-assisted radical prostatectomy   Prostate-specific antigen nadir   Biochemical recurrence  

摘要： Purpose The aim of the study is to evaluate the impact of having a nadir and persistently detectable ultrasensitive prostate-specific antigen (uPSA) between 0.01 and 0.1 ng/ml post-robot-assisted radical prostatectomy (RARP), on future biochemical recurrence (BCR). Methods We conducted a retrospective analysis of a prospectively maintained cohort of 1359 men who underwent RARP, between 2006 and 2019. Patients were followed with uPSA at 1, 3, 6, 9, 12, 18, 24, 30, 36 months and annually thereafter. We included patients with PSA nadir values between 0.01 and 0.1 ng/ml within 6 months of surgery and with at least 2 follow-up measurements within the same range. We divided patients based on their BCR status and analyzed uPSA changes. Multivariable Cox-regression models (CRMs) were used to analyze variables predicting BCR-free survival (BCR-FS). Results We identified 167 (12.3%) patients for analyses, with a mean follow-up time of 60.2 +/- 31.4 months. In our cohort, 5-year BCR-FS rate was 86%. Overall, 32 (19.1%) patients had BCR, with a mean time to BCR of 43.7 +/- 24.3 months. BCR-free patients had stable mean uPSA values <= 0.033 ng/ml, while patients who developed BCR showed a slowly rising trend over time, with a significant difference between groups starting at 9 months (p < 0.02). In multivariable CRMs, a rising uPSA starting at 9 months was an independent predictor of BCR (HR: 2.7;95% CI 1.6-3.82;p = 0.013). Conclusion In the present cohort, our results demonstrated that a considerable number of men have detectable uPSA values ranging between 0.01 and 0.1 ng/ml post-RARP. They can still be followed regularly to avoid patients' anxiety and salvage radiotherapy. Close follow-up is still required.

关键词： Biochemistry   Canine   Glucocorticoids   Laboratory analysis  

摘要： Prednisolone is used for treatment of inflammatory, allergic, neoplastic, and immune-mediated diseases in dogs. As a glucocorticoid, prednisolone has biochemical effects, which may interfere with the interpretation of biochemistry test results. The aim of this study is to investigate the effects of prednisolone treatment in an anti-inflammatory dose on common biochemical analytes in dogs and to evaluate the clinical relevance of the changes. Ten beagle dogs, enrolled in a cross-over study, were treated with oral prednisolone (1 mg/kg 24 h) for 10 days. Blood samples were collected at day 0, 1, 3, 6, 9, 10, 12, 16, and 20. Data was analyzed using a general linear model with time and treatment as fixed factors. Pairwise comparisons were done between prednisolone and control period for each dog and sampling. Significant results were further evaluated for clinical relevance using laboratory-specific reference intervals and reference change values (RCVs), when available. Statistically significant changes were observed for ALP activity and iron concentration, which increased to levels exceeding the RCV, and several results were outside reference intervals. Phosphate and bile acids increased significantly, while amylase, lipase, and cholesterol decreased significantly, but with mean/median results remaining within reference intervals. Anti-inflammatory prednisolone treatment did not induce significant changes in ALT, GLDH, GGT, cPLI, glucose, or calcium. Treatment with an anti-inflammatory dose of prednisolone induced changes in several analytes. Only the increases in ALP and iron were of such magnitude that they are expected to affect the clinical interpretation of test results. © 2021, The Author(s).

关键词： Gradient consistency test   Amino acid properties   Amino acid usage   Protein evolution  

摘要： Proteins can evolve by accumulating changes on amino acid sequences. These changes are mainly caused by missense mutations on its DNA coding sequences. Mutations with neutral or positive effects on fitness can be maintained while deleterious mutations tend to be eliminated by natural selection. Amino acid changes are influenced by the biophysical, chemical, and biological properties of amino acids. There is a multiplicity of amino acid properties that can influence the function and expression of proteins. Amino acid properties can be expressed into numerical indexes, which can help to predict functional and structural aspects of proteins and allow statistical inferences of selection pressure on amino acid usage. The accuracy of these analyses may be compromised by the existence of several numerical indexes that measure the same amino acid property, and the lack of objective parameters to determine the most accurate and biologically relevant index. In the present study, the gradient consistency test was used in order to estimate the magnitude of directional selection imparted by amino acid biochemical and biophysical properties on protein evolution.

关键词： Antimicrobial protein   L-amino acid oxidase   Interleukin (IL)-4-induced gene 1   Hydrogen peroxide   Metabolites   Biomarker  

摘要： Mucus layer that covers the body surface of various animal functions as a defense barrier against microbes, environmental xenobiotics, and predators. Previous studies have reported that L-amino acid oxidase (LAAO), present in several animal fluids, has potent properties against pathogenic bacteria, viruses, and parasites. LAAO catalyzes the oxidative deamination of specific L-amino acids with the generation of hydrogen peroxide and L-amino acid metabolites. Further, the generated hydrogen peroxide is involved in oxidation (direct effect) while the metabolites activate immune responses (indirect effect). Therefore, LAAO exhibits two different mechanisms of bioactivation. Previously, we described the selective, specific, and local oxidative and potent antibacterial actions of various LAAOs as potential therapeutic strategies. In this review, we focus on their biochemical features, enzymatic regulations, and biomedical applications with a view of describing their probable role as biochemical agents and biomarkers for microbial infections, cancer, and autoimmune-mediated diseases. We consider that LAAOs hold implications in biomedicine owing to their antimicrobial activity wherein they can be used in treatment of infectious diseases and as diagnostic biomarkers in the above-mentioned diseased conditions.